It looked like Jeb was responding to a photograph. Maybe of Dubya in handcuffs at the White House the night before when Trump invited he and Laura over "to look at Melania's Chtistmas decorations".
But Laura studied the doc with mouth agape for at least 5 - 10 seconds. After showing it to Jeb she turned to Dubya and asked "Is it true?"
Dubya, looking like a man who wanted the ground to open up and swallow him, responded "Yup" without turning to her, instead, looking at the floor.